I've had surgery many years back. A few weeks ago i hurt my knee when I walked into a hole I had not seen. There was swelling for a few days... Once the swelling went away I noticed a bump at the back of my knee. The bump itself is not painful, but my knee doesn't seem to really get better as a regular pain persists. I am keeping an eye on it, but I believe it is getting bigger. Will consult shortly, but any idea what this could be?